Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended		6 Months Ended
	Sep. 05, 2024	Jun. 15, 2024	Apr. 15, 2024	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Mar. 31, 2025
Asset Impairment Charges						$ 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings						1,100
Marketing and Advertising Expense				$ 89	$ 12	242	$ 12
Revenues				3,159	2,958	6,193	3,447
Redeemable Noncontrolling Interest, Equity, Carrying Amount				12,113		12,113		$ 13,880
Wireless Internet Services [Member]
Revenues				1,666	1,764	3,338	2,083
Fiber Internet Services [Member]
Revenues				1,016	773	1,946	879
Product and Service, Other [Member]
Revenues				$ 477	$ 421	$ 909	$ 485
Dissenting Shares [Member]
Stock Redeemed or Called During Period, Shares (in shares)	652,249		652,249
Payable, Common Stock Redeemed			$ 4,500
Share Price (in dollars per share)	$ 8.63		$ 6.94
Stock Redeemed or Called During Period, Value	$ 5,600
Amplex Holdings [Member]
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability		$ 502
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Right of Use Assets		$ 2,500
Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)				5 years		5 years
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)				10 years		10 years